A teenage boy with complex learning difficulties has been Tasered by police while he was at school.
Devon and Cornwall Police were called to Chelfham Senior School near Plymouth after reports of an alleged assault on a teacher.
The force confirmed officers deployed a Taser during the incident at 9.20pm on December 1, which involved three boys - a 15-year-old and two 14-year-olds - after reports that knives were brandished at officers.
But a solicitor has called into question the use of the device, in the circumstances.
Sophie Khan, a solicitor-advocate and legal director at Police Action Centre, said: "The police action may have been excessive.
"The use on children is only allowed if it is the only feasible method of restraining the child. It's only there if there are no other alternatives to restrain the child.
"Using a Taser on someone suffering some kind of behavioural difficulty or disability is something the policy or guidance doesn't allow."
The Independent Police Complaints Commission (IPCC) has not been contacted in relation to the incident at Chelfham, in Bere Alston.
The teacher was treated at the scene by paramedics for chest and head injuries before being taken to Derriford Hospital.
All three boys involved in the incident were jointly charged with affray and will appear at Plymouth Magistrates' Court on December 20.
The school, which specialises in children with learning difficulties including behavioural, emotional and social difficulties and autism, is owned by the exclusive Priory Group, a private company better known for its addiction clinics favoured by celebrities.
Devon and Cornwall Police are being investigated by the IPCC over a separate incident in which a man, who doused himself in petrol, burst into flames when he was shot with a Taser.
Andrew Pimlott, 32, suffered horrific injuries in the confrontation outside his house and died in a hospital burns unit five days later.
Figures released to Parliament earlier this year showed armed officers discharged, targeted or threatened to use Tasers against youngsters more than 320 times in 2011 - an 11-fold increase from the first year they were cleared for use against under-18s in 2007.